The prior art encompasses the long human history of cartography and navigation up to and including recent technological innovations. Examples include the achievement of seaworthy timepieces, which revolutionized and made accessible exact and reliable readings of longitude, and satellite technology and the Global Positioning System (GPS), which have revolutionized navigation. The field currently makes use of computer technology and the capacity of computers for quickly processing huge amounts of data and displaying data and permutations thereof to human users. The prior art then, includes the fields of cartography and navigation, surveying, photography, aviation, electronics and at least the following computer or digital arts: digital scanning of photographic images and digital rectification of stereo imagery into 3-dimensional information; computer processing; computer input technology such as punch cards, disc drives, keyboards and pointing devices; computer output technology such as display terminals, disc drives and discs, printers, and other output devices; computer communication technology such as networks, modems, file transfer protocols; database technology; mathematical and geometrical computer algorithms; and software including but not limited to ArcView 3.2a, MapInfo, and other Computer Aided Drafting (CAD) and GIS software.
GIS systems store, retrieve and display topological and cartographic information. The topographic study may be a map having features of the geographic region including natural features, such as rivers, lakes, and the like, and man-made features, such as canals, bridges, roads, and the like.
In conventional GIS systems, roads and streets are represented by lines, which show the center of the street to varying degrees of accuracy depending on the information used. These lines are called street centerlines. Prior art GIS street databases represent streets (major and minor roads, highways, parkways, paved and unpaved, and the like) as street centerline vectors, where the vectors are digitized line segments in a digitized topographical map, wherein at least certain points correspond to fixed latitude and longitude coordinates.
Heretofore, GIS street centerline files incorporate address ranges as attributes of street vectors. Thus, a given street line segment in prior art applications may show or be capable of showing an address range, as illustrated in FIG. 1a, which represents the physical addresses that may be found on that section of road. A typical example is a street segment with the address ranges 2, 4 up to 98 on the even number side of the street and 1, 3 up to 99 on the odd number side of the street. Address ranges are typically assigned to street segments during database construction by an operator with reference to ZIP code and basic address-to-ZIP and street-name information. This type of information is broad and inexact. Human guesswork often comes into play in assigning a particular address range to a particular street segment. In prior art applications, an address range shown may actually be on the segment of the road where it is depicted, or it may be blocks or miles away on the same street. In the example shown in FIG. 1a, it is not possible to determine whether the street segment in question has 99 physical structures, 10, 1 or none.
In prior art applications, address matching software applications within GIS determine the latitude and longitude coordinates of a street address. In such applications, a user who wishes to determine the latitude and longitude coordinates of a particular address would be able to get no more exact than the coordinates of the assigned address range in the database, with the above mentioned caveat that at times the assigned range is incorrect.
There are mission-critical applications that require the correct and instantaneous display of latitude and longitude points for a given street address. Mission-critical applications include emergency response applications to accurately locate a car crash, fire or medical emergency. In emergency response, the dispatcher and responder need to locate the crisis quickly and accurately in order to respond within the window of time in which the emergency can be addressed. For instance, medical emergencies often involve a finite period of time during which medical attention can save Ate victim's life. Every minute and second that can be shaved off of response time increases the victim's chances for survival. In the case of fire response, time can also make the difference between life and death, and it can take a large fire engine a several minutes to change course or perform a U-turn, adding urgency to the responder setting out with accurate information.
Prior art GIS street databases are not capable of displaying exact, accurate physical locations of street addresses, thus, in mission-critical applications, these address range interpolation data models are not capable of meeting the need for an exact address location.
Therefore, there is a need for a GIS street database, which can display accurate locations of street addresses for use in environments that require pinpoint accuracy, such as emergency response. While emergency response has been used to illustrate the capacities and limitation of prior art applications, it is by no means the only area for application of the present invention. As set forth below, there are many market sectors where accurate location of clients, prospects and capital have broad application.